This description will explain the planetary retrograde motion of Venus, which is the apparent backward motion of the planet in relation to Earth. This phenomenon occurs when Venus passes between Earth and the Sun, and is visible from Earth as a looping motion in the night sky. During this time, Venus
Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is, the central object. It may also describe other motions such as precession or nutation of an object's rotational axis. Prograde or direct motion is more normal motion in the same direction as the primary rotates. However, "retrograde" and "prograde" can also refer to an object other than the primary if so described. The direction of rotation is determined by an inertial frame of reference, such as distant fixed stars.